State profile · Above national median SD

Iowa bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Iowa — drawn straight from the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition
20.0%
Structurally deficient

Total Bridges

20,753

Public highway bridges in Iowa

Good Condition

36.5%

7,582 bridges rated 7-9

-13.5pp vs 50% benchmark

Poor Condition

20.0%

4,153 bridges rated 0-4

Structurally Deficient

20.0%

4,153 bridges flagged for repair priority

13.0pp vs national avg 7.0%

Iowa vs national bridge condition

Iowa — Good condition share 36.5%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Iowa — Structurally deficient share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Iowa36.534476943092564%38.39444899532597%20.011564593070883%20.011564593070883%GoodFairPoorStructurally Deficient
Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Counties (99)

Adair 208 Adams 147 Allamakee 170 Appanoose 159 Audubon 161 Benton 327 Black Hawk 411 Boone 119 Bremer 220 Buchanan 281 Buena Vista 140 Butler 261 Calhoun 171 Carroll 223 Cass 237 Cedar 265 Cerro Gordo 210 Cherokee 223 Chickasaw 268 Clarke 150 Clay 138 Clayton 214 Clinton 325 Crawford 242 Dallas 154 Davis 156 Decatur 178 Delaware 254 Des Moines 156 Dickinson 73 Dubuque 304 Emmet 70 Fayette 288 Floyd 195 Franklin 214 Fremont 133 Greene 150 Grundy 270 Guthrie 236 Hamilton 134 Hancock 128 Hardin 211 Harrison 162 Henry 144 Howard 193 Humboldt 70 Ida 164 Iowa 189 Jackson 209 Jasper 321 Jefferson 142 Johnson 317 Jones 215 Keokuk 152 Kossuth 256 Lee 185 Linn 428 Louisa 134 Lucas 186 Lyon 241 Madison 221 Mahaska 219 Marion 204 Marshall 283 Mills 170 Mitchell 160 Monona 125 Monroe 126 Montgomery 184 Muscatine 127 O'Brien 229 Osceola 176 Page 185 Palo Alto 114 Plymouth 407 Pocahontas 186 Polk 415 Pottawattamie 469 Poweshiek 221 Ringgold 206 Sac 188 Scott 212 Shelby 194 Sioux 429 Story 262 Tama 307 Taylor 220 Union 153 Van Buren 142 Wapello 160 Warren 231 Washington 203 Wayne 163 Webster 179 Winnebago 48 Winneshiek 317 Woodbury 379 Worth 89 Wright 168

Iowa vs nearby ranks

Adjacent states on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Iowa on the same metric.

54

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

46

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

19

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

78

Virgin Islands

29.17% top marginal rate
Structure
Progressive
Burden @ $100K
$24

Bridges Needing Most Attention in Iowa

Six lowest-condition bridges in Iowa, ranked by composite NBI rating. Each is inspected at least every 24 months.

270TH STREET

Structurally Deficient

Over: ROSE BRANCH

071343401, Adams, IA

Built 1976 Load: 2.7 t ADT: 79

LOCAL

Poor

Over: CREEK

078342601, Audubon, IA

Built 1935 Load: 2.7 t ADT: 21

KLINE RD

Structurally Deficient

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Structurally Deficient

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Structurally Deficient

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Structurally Deficient

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

1860 210TH ST

Poor

Over: EAST IOWA RIVER

095241201, Hancock, IA

Built 1967 Load: 8.0 t ADT: 259

LOCAL

Poor

Over: TIPTON CREEK

087212602, Hardin, IA

Built 1983 Load: 8.0 t ADT: 51

LCL-400TH ST

Poor

Over: INDIAN CREEK

072401102, Mills, IA

Built 1940 Load: 8.0 t ADT: 26

XAVIER AVENUE

Poor

Over: E. FORK E NODAWAY RIVER

073322404, Adams, IA

Built 1974 Load: 8.1 t ADT: 40

LOCAL

Poor

Over: W FK W NISHNABOTNA RIVER

082381201, Crawford, IA

Built 1945 Load: 8.1 t ADT: 30

130TH ST

Poor

Over: W BR FLOYD RIVER

093451901, Plymouth, IA

Built 1900 Load: 8.1 t ADT: 20

FM

Poor

Over: BRANCH, SKUNK RIVER

081231301, Polk, IA

Built 1968 Load: 8.1 t ADT: 139

LOCAL

Poor

Over: WALNUT CREEK

069303506, Ringgold, IA

Built 1956 Load: 8.1 t ADT: 15

LOCAL

Poor

Over: LOCAL STREAM

073050802, Henry, IA

Built 1968 Load: 8.3 t ADT: 41

LOCAL

Poor

Over: BR.WALNUT CREEK

073082003, Jefferson, IA

Built 1950 Load: 8.3 t ADT: 34

LCL-400TH ST

Poor

Over: HUNTERS BRANCH

071402602, Mills, IA

Built 1965 Load: 8.3 t ADT: 26

TEAK AVE

Poor

Over: STREAM

070362104, Page, IA

Built 1999 Load: 8.3 t ADT: 5

LOCAL

Poor

Over: WEST 102 RIVER

070350103, Taylor, IA

Built 1955 Load: 8.3 t ADT: 11

LOCAL

Poor

Over: CREEK

090E20905, Dubuque, IA

Built 1925 Load: 8.4 t ADT: 44

LOCAL

Poor

Over: SMALL STREAM

081333002, Guthrie, IA

Built 1987 Load: 8.4 t ADT: 29

LOCAL RD

Poor

Over: MIDDLE RIVER

075281302, Madison, IA

Built 1948 Load: 8.4 t ADT: 45

LOCAL

Poor

Over: MOON CREEK

077150101, Mahaska, IA

Built 1952 Load: 8.4 t ADT: 40

LOCAL

Poor

Over: MOSQUITO CREEK

080403505, Shelby, IA

Built 1930 Load: 8.4 t ADT: 26

LOCAL

Poor

Over: LITTLE CEDAR CREEK

070083204, Van Buren, IA

Built 1961 Load: 8.4 t ADT: 21

FM

Poor

Over: FLOOD CREEK

096173101, Floyd, IA

Built 1969 Load: 8.5 t ADT: 88

220TH ST

Poor

Over: EAST BR INDIAN CREEK

083220201, Story, IA

Built 1900 Load: 8.5 t ADT: 34

LOC 150TH ST

Poor

Over: OTTER CR

090093201, Buchanan, IA

Built 1953 Load: 8.6 t ADT: 130

LOCAL

Poor

Over: STREAM

078133401, Poweshiek, IA

Built 1920 Load: 8.6 t ADT: 11

LOCAL

Poor

Over: WALNUT CREEK

081151902, Poweshiek, IA

Built 1928 Load: 8.6 t ADT: 15

LOCAL

Poor

Over: WEST 102 RIVER

070341801, Taylor, IA

Built 1965 Load: 8.6 t ADT: 11

LYNX AVE

Poor

Over: PLYMOUTH CREEK

091450402, Plymouth, IA

Built 1960 Load: 8.7 t ADT: 26

LOCAL

Poor

Over: TROUBLESOME CREEK

079332901, Guthrie, IA

Built 1990 Load: 8.8 t ADT: 11

LOCAL ROAD

Poor

Over: BRANCH SUGAR CREEK

073071605, Henry, IA

Built 1917 Load: 8.8 t ADT: 21

E 5TH STREET

Poor

Over: OVERFLOW IOWA RIVER

082150303, Tama, IA

Built 1900 Load: 8.8 t ADT: 320

LOCAL

Poor

Over: WEST 102 RIVER

069352203, Taylor, IA

Built 1972 Load: 8.8 t ADT: 15

LOCAL

Poor

Over: EAST LONG CREEK

072273601, Clarke, IA

Built 1986 Load: 8.9 t ADT: 26

LOCAL

Poor

Over: SNIPE CREEK

082181302, Marshall, IA

Built 1915 Load: 8.9 t ADT: 51

LOCAL

Poor

Over: DD#16

089351302, Sac, IA

Built 1924 Load: 8.9 t ADT: 45

LOCAL

Poor

Over: DRAINAGE DITCH 11-13

090260804, Wright, IA

Built 1927 Load: 8.9 t ADT: 72

LOCAL

Poor

Over: SO WHITE BREAST CREEK

071240805, Clarke, IA

Built 1981 Load: 9.0 t ADT: 15

FM

Poor

Over: BRANCH OTTER CREEK

073243103, Clarke, IA

Built 1951 Load: 9.0 t ADT: 40

ECHO VALLEY RD.

Poor

Over: OTTER CREEK

094082207, Fayette, IA

Built 1969 Load: 9.0 t ADT: 88

LOCAL

Poor

Over: TIPTON CREEK

087210802, Hardin, IA

Built 1984 Load: 9.0 t ADT: 30

FM

Poor

Over: SMALL STREAM

097451501, Sioux, IA

Built 1962 Load: 9.0 t ADT: 34

LOCAL

Poor

Over: STREAM

067181603, Appanoose, IA

Built 1995 Load: 9.1 t ADT: 51

GRANNIS RD.

Poor

Over: GRANNIS CR

093083605, Fayette, IA

Built 1951 Load: 9.1 t ADT: 29

175TH ST

Poor

Over: VOLGA RIVER

093101103, Fayette, IA

Built 1955 Load: 9.1 t ADT: 11

315TH ST

Poor

Over: MOSQUITO CREEK

078412003, Harrison, IA

Built 1930 Load: 9.1 t ADT: 20

FM

Poor

Over: N COAL CREEK

074170406, Mahaska, IA

Built 1953 Load: 9.1 t ADT: 20

FM

Poor

Over: LOCAL CREEK

071163103, Monroe, IA

Built 1958 Load: 9.1 t ADT: 110

FM

Poor

Over: OLD CHANNEL DES MOINES R

094310803, Palo Alto, IA

Built 1956 Load: 9.1 t ADT: 46

LOCAL

Poor

Over: DRAINAGE DITCH #29

090333102, Pocahontas, IA

Built 1920 Load: 9.1 t ADT: 26

LOCAL

Poor

Over: STREAM

087361204, Sac, IA

Built 1924 Load: 9.1 t ADT: 50

580TH AVE

Poor

Over: LONG DICK CREEK

085231602, Story, IA

Built 1964 Load: 9.1 t ADT: 50

LOCAL

Poor

Over: WEST BRANCH 102

069340604, Taylor, IA

Built 1971 Load: 9.1 t ADT: 11

Showing 16,751-16,800 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

Read our methodology — how this data is sourced, computed, and verified.